Study On Nutrition, Flavor And Product Of Fatty Goose Liver

The fatty goose liver (foie gras) is known as one of the world's three major cuisines.However, few researches have been done on the nutrition, volatile compounds and products of fatty goose liver. So the thesis is to do some research on the nutritive substances and identify the ones that are beneficial to human bodies, which will provide theoretical support for the foie gras grading standards, serve to analysis the special aroma compounds and study the processing technology of fatty goose liver made in China, in order to develop a marketable product—goose liver catsup. Main results are as follows:1. Main nutrient composition data of fatty goose liver was obtained. Using frozen fatty goose liver as raw materials, goose liver fat content and fatty acid composition and content, protein content, trace elements, moisture and ash were analyzed by the standard methods. Every100grams of goose liver (premium) contains fat59.55g, of which:saturated fatty acids (SFA)38.38%, monounsaturated fatty acids (MUFA)60.69%and polyunsaturated fatty acids (PUFA)0.93%; protein5.64g; water30.87g; ash0.49g; trace elements calcium, iron, zinc, and copper:4.68mg,3.15mg,1.73mg and0.36mg, respectively.2. There are significant difference (P<0.05) in the fat content among the livers of all levels, with premium goose liver, A level goose liver and B level goose liver59.55%,49.20%and42.95%respectively, which supports the present goose liver grading standards whose main indicators are existing appearance and liver weight. As for the trace elements, iron had a positive while zinc had a negative correlation with fatty goose liver, which can be used as additional indicators of goose liver grading.3. The volatile compounds in fatty goose liver was extracted by simultaneous distillation extraction (SDE) and then analyzed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry(GC-O). Totally41volatile flavor compounds were identified and they were8hydrocarbons,4alcohols,2phenols,7aldehydes,5ketones,1acids,7ester,7others, and3not identified. Among these compounds, hexanal,2-ethylcyclohexanol, nonanal,2-Pentadecanone,6,10,14-trimethyl-tetradecanal, di-n-octyl phthalate were the important volatile flavor compounds in fatty goose liver.4. To perfect the flavor, the procedure of the enzymatic hydrolysis of proteins from goose liver catsup by flavourzyme was studied and hydrolyzing degree of goose liver catsup protein were evaluated, and the result showed that optimal conditions of E:S ratio, hydrolyzing time, starting pH and temperature for this hydrolysis procedure were established as0.342:100,3.59h,6.42, and57.60℃respectively, which proved that the flavourzyme could improve the flavor of goose liver catsup.5. With frozen domestic goose liver as raw material, a new technique was developed to produce goose liver catsup, By making sense evaluation and the cross-link test analysis the best technical prescription is:goose liver:water:emulsifiers:thickener=100:100:1.5:1, and mixing time:4min. Sensory evaluation, physical and chemical analysis, microbe counting and low-temperature preservation experiment were carried out under this prescription to assess the products. The results showed; the goose liver catsup can was consistent with corresponding criterion, and there was no sign of deterioration within shelf-life storage。...